You can't claim that condition for a disability. I'm assuming your a reservist or guardsman. When a reservist gets injured and they are not in a pay status (drill or AT), anything that happens is on them and not the military.
If you were AGR at the time of the accident, and you weren't doing something stupid, then you should be covered. If the IO didn't realize that you were AGR, he may have filled out the LOD as if you were an M-Day soldier. An accident while on active duty should be covered. Unless you were engaged in "willful misconduct". That term can screw you every time. I would definitely talk to the IO and ask him some questions.